1. Field of the Invention
This invention relates generally to a sand-blasting device, and more particularly to a sand-blasting apparatus which is provided with a unique return-vacuum system that includes both a continuous low-pressure return vacuum and a selective high-pressure vacuum.
2. Description of the Prior Art
As is well known in the art, various problems and difficulties are encountered in providing suitable means for establishing a clean-air environment while sand-blasting, especially in closed or confined areas.
There are several types of known sand-blasting systems; however, these devices have features that restrict their use to certain sand-blasting conditions and circumstances. Many of the known devices are complicated to operate, often requiring two or more operators, and others are prohibitively expensive to maintain, particularly under limited use.
Accordingly, high-pressure sand-blasting equipment very often requires a water mixture which cannot be used in closed or confined areas. Some sand-blasting devices have various means for saving the used sand so as to be recycled. However, to the applicant's knowledge, there is no device of the character herein disclosed that overcomes many of the existing problems inherent in known sand-blasting apparatuses.